The invention relates to flexible channel-shaped sealing, finishing and guide strips for use as draft excluding seals, beadings, window channels, flange finishers (for covering welded flanges) and the like. Such strips are hereinafter referred to generically as "sealing strips", and are particularly, though not exclusively, for use in vehicle construction.
Sealing strips are known comprising a metal core or carrier which is covered by or embedded in elastomeric material. Known forms of metal core or carrier are made of wire or strip metal. Flexibility of the sealing strip about its longitudinal axis is highly desirable and, in an attempt to achieve this, it is known to make a metal carrier from a plurality of side-by-side U-shaped metal strip elements spaced from each other and either entirely disconnected or connected together by short connecting links, the carrier so formed being embedded in elastomeric material, for example by extrusion.
Such metal carriers suffer from a number of advantages. For example, the gaps between the metal carrier elements may cause the shape of the elements to become noticeable on the external surface of the elastomeric material giving an unacceptable or displeasing appearance.
On the other hand, a metal carrier made of continuous channel-shaped metal is unsatisfactory because it will have insufficient flexibility.
It is also desirable that a sealing strip shall be capable of some compression or extension lengthwise in order to provide take-up for length tolerance. A metal carrier comprising continuous channel-shaped metal, or one comprising spaced elements connected by short connecting links, may well have no, or insufficient, compressibility or extensibility.
It is an object of the invention to provide an improved metal carrier for a channel-shaped sealing strip.
A more specific object of the invention is to provide a metal carrier for a channel-shaped sealing strip which allows some lengthwise compressibility and extensibility for the sealing strip and also reduces the possibility of individual elements of the sealing strip becoming visible externally of the sealing strip.
A further object of the invention is to provide a metal carrier with good strength and flexibility and yet which is economical in the metal used.